Reav3 goes more in depth on the art direction they took with Swain
"Hey guys,
In retrospect I think my response was pretty bad because I just described the teams feeling on why we think Swains new look reflects his new theme/direction but I didn't really go into the foundations of the Swain VGU that led to that reasoning which I think made it end up pretty shallow and I apologize for that. It also came across as "Because lore" which wasn't the intention as we choose the lore when we make the champion, as long as it makes sense within the IP of course. I also don't want to give away too much of the new lore/bio stuff before it is released.
Let's start from the beginning though. Whenever we make a new champion or VGU we highly value thematic cohesion. We generally start with a high level theme or archetype we are trying to achieve and then Art, Narrative and gameplay design forms pillars in order to support that theme. One of the problems with pre-rework Swain was that he wasn't very thematically cohesive, and his source of power wasn't very clear either (though that in unrelated to the hair discussion.) Early on we decided that it was important that Swain felt like the ruler of Noxus and we wanted his high level theme to be a Warlock Dictator. We felt it was very important that he feels like he is in control on the demon which is why he doesn't fully transform into a bird when he ults. We didn't feel chained to the lore and of course we could have changed this but in the end we felt it was important that Swain was in control of the demon and that it wasn't controlling or corrupting him. Swain is not Kayn or Varus. This goes back to his theme of being bad ass enough to bend a nation to his will, on his own. As for the hair, the team does feel the long hair adds the sophistication/intellect feeling that is also very important to his theme, which also comes across in his lore/personality and VO. Once again we aren't bending to any lore, we created the lore in service of what we believe was a strong thematic direction for Swain. Short hair lends itself more to a rugged, war general, and less of a Intellectual Warlock Dictator. Jarven is probably closer to the rugged War General Archetype rather then Warlock Dictator which is more cohesive with a ranged/mage champion.
Tbh the changes would not be difficult to make, that is not the issue. We don't want to make changes we feel will lessen his thematic cohesion when that was one of the primary goals of the rework from the beginning.
One thing I will note however is that I do think the hair is coming off more white in the splash then grey which is leading him to look more young/malfoy then intended. In the model his hair looks much more grey. Our intention was that young Swain had black hair but it turned grey as he got older. In fact for a large portion of development Swain did have black hair but many people felt he looked way to young to be leading a powerful nation like Noxus. We will look into this."